Hypoallergenic derivatives of Fel d 1 obtained by rational reassembly for allergy vaccination and tolerance induction. Issue 6 (June 2014)

• Record Type: Journal Article
• Authors: Curin, M.; Weber, M.; Thalhamer, T.; Swoboda, I.; Focke‐Tejkl, M.; Blatt, K.; Valent, P.; Marth, K.; Garmatiuk, T.; Grönlund, H.; Thalhamer, J.; Spitzauer, S.; Valenta, R.
• Is Part Of: Clinical & experimental allergy. Volume 44:Issue 6(2014:Jun.)
• Page Start: 882
• Page End: 894
• Publication Date: 2014-06
• Subjects: Allergy -- Periodicals; Immunology -- Periodicals; 616.97
• DOI: 10.1111/cea.12294
• Languages: English
• ISSNs: 0954-7894

Abstract

<abstract abstract-type="main" id="cea12294-abs-0001"> <title>Summary</title> <sec id="cea12294-sec-0001" sec-type="section"> <title>Background and objective</title> <p>The major cat allergen Fel d 1 represents one of the most important respiratory allergens. Aim of this study was to engineer recombinant Fel d 1 derivatives with reduced IgE reactivity and preserved T cell epitopes for vaccination and tolerance induction.</p> </sec> <sec id="cea12294-sec-0002" sec-type="section"> <title>Methods</title> <p>Seven recombinant mosaic proteins were generated by reassembly of non‐IgE‐reactive peptides of Fel d 1 which contained the sequence elements for induction of allergen‐specific blocking IgG antibodies and T cell epitopes. Mosaic proteins were expressed in <italic>Escherichia coli</italic> using codon‐optimized synthetic genes and compared with Fel d 1 regarding structural fold by circular dichroism, IgE‐binding capacity, activation of allergic patients' basophils and ability to induce allergen‐specific blocking IgG antibodies upon immunization.</p> </sec> <sec id="cea12294-sec-0003" sec-type="section"> <title>Results</title> <p>Although each of the mosaic proteins had lost the alpha‐helical fold typical for Fel d 1, a strong reduction in IgE reactivity as well as allergenic activity in basophil activation assays was only obtained for three constructs, two reassembled fragments (Fel d 1 MB, Fel d 1 MC) and a fusion of the latter two (Fel d 1 MF) in which the cysteines of Fel d 1 MC were replaced by serines. Immunization of rabbits with Fel d 1 MB, MC and MF induced high levels of IgG antibodies that inhibited IgE reactivity of cat‐allergic patients to Fel d 1 in a comparable manner as IgG induced with the wild‐type allergen.</p> </sec> <sec id="cea12294-sec-0004" sec-type="section"> <title>Conclusions</title> <p>We report the development of hypoallergenic reassembled Fel d 1 proteins suitable for vaccination and tolerance induction in cat‐allergic patients.</p> </sec> </abstract>